The White House released
a preliminary report on the intelligence failures leading up
to the attempted attack on Christmas. The majority of the blame
seems to lie with individuals not doing their jobs, rather than
systemic flaws.

But shoddy software also appears to have played a role. From the
report:

Mr. Abdulmutallab possessed a U.S. visa, but this fact was not
correlated with the concerns of Mr. Abdulmutallab's father about
Mr. Abdulmutallab's potential radicalization. A misspelling of
Mr. Abdulmutallab's name initially resulted in the State
Department believing he did not have a valid U.S. visa. A
determination to revoke his visa however would have only occurred
if there had been a successful integration of intelligence by the
CT [counterterrorism] community, resulting in his being
watchlisted.

As Noah Shachtman,
writing for the Danger Room, points out, this is a fairly
simple problem that commercial software has solved -- misspelling
a name in Google does not prevent you from finding the correct
search results.

That the intelligence community uses software that can't
handle misspellings is alarming, as Arabic names often have more
than one accepted spelling when transliterated into our alphabet.